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To discuss the decision-making scheme of crowding risk management during the COVID-19 pandemic, this paper constructs an evolutionary game model based on the changes of pedestrian and government strategies, and simulates the strategy selection under different states. The results show that under the condition of pedestrian rationality, when the difference between the benefits and costs of the government's active response strategy is less than the benefits of inaction, the government will choose the strategy of inaction. If the benefit of rational action is less than the additional benefit of irrational action, pedestrians will choose irrational action. By establishing the replication dynamic equations of governments and pedestrians, the stability strategy of the system is analyzed. It is found that the values of R1, R2, R3, R4, R5, C1, C2, C3, C4, C5, C6, C7 will affect the strategy choices of the players, and how to measure the benefits and costs under different circumstances becomes the key to the problem. These findings provide a theoretical basis for the risk control decision of human crowding during the COVID-19 epidemic. © 2023 SPIE.
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Background & Aim: The long-term effects of human mesenchymal stem cell (MSC) treatment on COVID-19 patients have not been fully characterized. The aim of this study was to evaluate the safety and efficacy of a MSC treatment administered to severe COVID-19 patients enrolled in a randomized, double-blind, placebo-controlled clinical trial (NCT 04288102). Methods, Results & Conclusion(s): A total of 100 patients experiencing severe COVID-19 received either MSC treatment (n = 65, 4x107 cells per infusion) or a placebo (n = 35) combined with standard of care on days 0, 3, and 6. Patients were subsequently evaluated 18 and 24 months after treatment to evaluate the long-term safety and efficacy of the MSC treatment. The outcomes measured included: 6-minute walking distance (6-MWD), lung imaging, quality of life according to the Short Form 36 questionnaire, COVID-19-related symptoms, titers of SARS-CoV-2 neutralizing antibodies, MSC-related adverse events (AEs), and tumor markers. Two years after treatment, a marginally smaller proportion of patients had a 6-MWD below the lower limit of the normal range in the MSC group than in the placebo group (OR = 0.19, 95% CI: 0.04-0.80, Fisher's exact test, p = 0.015). On the SF-36 questionnaire, a marginally higher general health score was received by the MSC group at month 18 compared with the placebo group (50.00 vs. 35.00;95% CI: 0.00-20.00, Wilcoxon rank sum test, p = 0.016). In contrast, there were no differences in the total severity score of lung imaging or the titer of neutralizing antibodies between the two groups. Meanwhile, there were no MSC-related AEs reported at the 18- or 24-month follow-ups. The serum levels of most of the tumor markers examined remained within normal ranges and were similar between the MSC and placebo groups. Long-term safety was observed for the COVID-19 patients who received MSC treatment. Yet few sustained efficacy of MSC treatment was observed at the end of the 2-year follow-up period. Funding(s): The National Key Research and Development Program of China (2022YFA1105604, 2020YFC0860900), the specific research fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202216) and the Fund of National Clinical Center for Infectious Diseases, PLA General Hospital (NCRCID202105,413FZT6). [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy
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PurposeThis paper aims to investigate how value drivers of internet medical business model affect value creation through a configurational approach. The internet medical business model (IMBM) is such a business model that integrates online and offline medical services with the driving force of internet technologies covering prediagnosis, in-diagnosis and postdiagnosis. The outbreak of COVID-19 and the support of national policies have boosted the development of internet health care. However, there are still many challenges in practice, such as the unclear innovation path, as well as difficulties in landing and profiting. Academic research has not yet provided sufficient theoretical insights. Therefore, to better explain and guide practice, it is urgent to clarify the innovation path and mechanism of value creation for IMBM. Design/methodology/approachBased on the sample of 58 internet medical firms in China, this paper adopts fuzzy-set qualitative comparative analysis (fsQCA) to explore the configurational effects of IMBM's value drivers on value creation. FindingsBuilding on the business model canvas and the characteristics of internet health care, five value drivers of IMBM are identified, namely, functional value proposition, emotional value proposition, user involvement, resource capabilities and connection properties. And the five value drivers form three configurations, which are, respectively, labeled as resource-driven configuration, user-operated configuration and product-combined configuration. From the perspective of the integration of traditional and emerging theories, such as resource-based view, internet economics and value cocreation, each configuration leads to value creation and improves value results with different mechanisms behind it. Originality/valueFirst, combined with the business model canvas and the characteristics of internet health care, this paper identifies five value drivers of IMBM, thus improving the relevant research on internet health care. Second, based on the configurational effects, this paper discusses the mechanism behind the configurational effects of IMBM's value drivers on value creation, thus expanding relevant research on the value creation of business models. Third, applying fsQCA and combining the advantages of qualitative research and quantitative research, this paper adds to the configurations of IMBM's value drivers that achieve high-value results.
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Background The global spread of coronavirus disease 2019 (COVID-19) continues to threaten human health security, exerting considerable pressure on healthcare systems worldwide. While prognostic models for COVID-19 hospitalized or intensive care patients are currently available, prognostic models developed for large cohorts of thousands of individuals are still lacking. Methods Between February 4 and April 16, 2020, we enrolled 3,974 patients admitted with COVID-19 disease in the Wuhan Huo-Shen-Shan Hospital and the Maternal and Child Hospital, Hubei Province, China. (1) Screening of key prognostic factors: A univariate Cox regression analysis was performed on 2,649 patients in the training set, and factors affecting prognosis were initially screened. Subsequently, a random survival forest model was established through machine analysis to further screen for factors that are important for prognosis. Finally, multivariate Cox regression analysis was used to determine the synergy among various factors related to prognosis. (2) Establishment of a scoring system: The nomogram algorithm established a COVID-19 patient death risk assessment scoring system for the nine selected key prognostic factors, calculated the C index, drew calibration curves and drew training set patient survival curves. (3) Verification of the scoring system: The scoring system assessed 1,325 patients in the test set, splitting them into high- and low-risk groups, calculated the C-index, and drew calibration and survival curves. Results The cross-sectional study found that age, clinical classification, sex, pulmonary insufficiency, hypoproteinemia, and four other factors (underlying diseases: blood diseases, malignant tumor;complications: digestive tract bleeding, heart dysfunction) have important significance for the prognosis of the enrolled patients with COVID-19. Herein, we report the discovery of the effects of hypoproteinemia and hematological diseases on the prognosis of COVID-19. Meanwhile, the scoring system established here can effectively evaluate objective scores for the early prognoses of patients with COVID-19 and can divide them into high- and low-risk groups (using a scoring threshold of 117.77, a score below which is considered low risk). The efficacy of the system was better than that of clinical classification using the current COVID-19 guidelines (C indexes, 0.95 vs. 0.89). Conclusions Age, clinical typing, sex, pulmonary insufficiency, hypoproteinemia, and four other factors were important for COVID-19 survival. Compared with general statistical methods, this method can quickly and accurately screen out the relevant factors affecting prognosis, provide an order of importance, and establish a scoring system based on the nomogram model, which is of great clinical significance. © Wolters Kluwer Health, Inc. All rights reserved.
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Background The continued spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains an international public health emergency, resulting in a significant global disease burden. The long-term effects of SARS-CoV-2 infection in humans and the long-term prognosis of patients with coronavirus disease 2019 (COVID-19) after discharge remain unclear. We aimed to assess the quality of life (QoL) and sequelae in patients with COVID-19 after discharge from the hospital by conducting multiple follow-up visits to understand the long-term effects of SARS-CoV-2 on patients' health and its possible influencing factors. Methods COVID-19 patients discharged from Huoshenshan Hospital (Wuhan, China) between February 15 and April 5, 2020, were followed up at 6, 9, and 12 months after discharge. They completed questionnaires on postdischarge QoL and sequelae under the guidance of medical staff with professional training. The demographic and clinical characteristics of the COVID-19 patients were analyzed using descriptive statistics. A generalized estimating equation model was used to analyze the QoL-related factors. The χ2 test (or Fisher exact test) and multivariate logistic regression analysis were used to analyze the sequelae and influencing factors. Results A total of 175 patients participated in at least 1 follow-up visit, and 120 completed all 3 follow-up visits. Patients diagnosed with severe and critically ill COVID-19 had worse mental conditions (χ2 = 7.653, P = 0.022) than those with the nonsevere type (not severe or critical) and were more likely to feel fatigued (χ2 = 4.836, P = 0.028). Female patients had a higher risk of sleep disturbance (χ2 = 10.026, P = 0.002) and dyspnea (χ2 = 5.672, P = 0.017) and had more difficulty returning to their original work and life (χ2 = 8.922, P = 0.003) than male patients. Patients with diabetes had a worse appetite (χ2 = 4.669, P = 0.031) and were more prone to sleep disturbance (χ2 = 4.417, P = 0.036) after discharge. The proportion of patients with at least 1 sequela increased from 29.76% (50/168) at 6 months to 51.11% (69/135) at 9 months (χ2 = 14.305, P < 0.001). Compared with the nonsevere type, patients diagnosed with severe and critically ill COVID-19 had an odds ratio (OR) of 4.325 (95% confidence interval [CI], 1.215-15.401) for memory decline. Female patients had an OR of 4.632 (95% CI, 1.716-12.501) for joint or muscle pain. Patients with hypertension had an OR of 3.014 (95% CI, 1.193-7.615) for joint or muscle pain. Conclusion One year after discharge, there were still some patients with varying degrees of decline in QoL and sequelae, which occurred in all follow-up visits. Moreover, QoL and sequelae after discharge were related to sex, clinical classification of COVID-19, and underlying diseases. © Wolters Kluwer Health, Inc. All rights reserved.
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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in numerous confirmed cases and deaths worldwide. Recent studies have shown that people living with HIV (PLWH) are prone to develop severe illness and poor outcomes if they experience coronavirus disease 2019 (COVID-19), especially those with uncontrolled viremia and low CD4 T-cell count. Therefore, many countries prioritized PLWH for COVID-19 vaccination. However, lower magnitude or faster waning humoral immune responses elicited by other vaccines have been documented in PLWH, raising concerns regarding the efficacy of the COVID-19 vaccine in these specific populations. Here, we summarize the current progress in the immunogenicity and efficacy of different types of SARS-CoV-2 vaccinations in PLWH and highlight several challenges faced by PLWH in the current COVID-19 pandemics. © Wolters Kluwer Health, Inc. All rights reserved.
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Colchicine is an alkaloid with antitumor effect isolated from Colchicum autumnale plants, it has been reported in multiple studies as a potential treatment for coronavirus disease-19 and this study applied network pharmacology and bioinformatics analysis to explore the potential mechanism of colchicine against non-small cell lung cancer and coronavirus disease-19. The R software was used to determine the differentially expressed genes of non-small cell lung cancer/coronavirus disease-19, and carry out prognostic analysis and clinical analysis of the differentially expressed genes, the targets of colchicine were obtained from various databases, the protein-protein interaction network of intersection targets of colchicine and non-small cell lung cancer/coronavirus disease-19 was constructed, enrichment analysis of gene ontology and kyoto encyclopedia of genes and genomes pathways was performed by Metascape database and the molecular docking and molecular dynamics simulation were completed. We obtained a total of 716 differentially expressed genes and identified 13 potential prognostic genes associated with the clinical characterization of non-small cell lung cancer/coronavirus disease-19 patients. C-C motif chemokine ligand 2, toll like receptor 4, intercellular adhesion molecule 1, peroxisome proliferator activated receptor gamma, interleukin 17A, interferon gamma, angiotensin I converting enzyme, fos proto-oncogene, nuclear factor kappa B inhibitor alpha, TIMP metallopeptidase inhibitor 1 and secreted phosphoprotein 1 were core targets. The intersection targets of colchicine and non-small cell lung cancer/coronavirus disease-19 were mainly enriched in biological processes such as inflammatory response, response to cytokine and response to lipopolysaccharide, as well as signal pathways such as interleukin 17 signaling pathway, hypoxia inducible factor 1 signaling pathway and nucleotide binding oligomerization domain-like receptor signaling pathway. The results of molecular docking showed that the colchicine is better combined with the core targets. Analysis of molecular dynamics simulation showed that the protein and ligand form a stabilizing effect. Based on bioinformatics analysis and network pharmacology, we obtained biomarkers that may be used for the prognosis of non-small cell lung cancer/coronavirus disease-19 patients and revealed that colchicine may play a potential role in the treatment of non-small cell lung cancer/coronavirus disease-19 by regulating multiple targets and multiple signaling pathways and participating in multiple biological processes.
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By regarding the Chinese financial and economic sectors as a system, this article studies the stock volatility spillover in the system and explores its effects on the overall performance of the macroeconomy in China. The recent outbreak of COVID-19, U.S.-China trade friction, and three historical financial turbulences are involved to distinguish the changes in the spillover in these distinct crises, which has seldom been unveiled in the literature. By considering that the stock volatility spillover may vary over distinct timescales, the spillovers are disclosed through innovatively constructing the multi-scale spillover networks, followed by connectedness computation, based on variational mode decomposition (VMD) and generalized vector autoregression (GVAR) process. Our empirical analysis first demonstrates the different levels of increases in the total sectoral volatility spillover and changes in the roles of the sectors in the system under the aforementioned crises. Besides, the increases in the sectoral spillover in the long-term are verified to negatively impact the macroeconomy and can thereby act as warning signals.
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In increasingly energy-dependent world, there is a question mark over the viability of fossil fuel resources. To tackle this issue, an integrated poly-generation system based on concentrated solar power is proposed to feed in the city grid and produce hydrogen as a clean energy carrier. Concerning the COVID-19 outbreak, all countries are in dire need of oxygen. Therefore, the produced oxygen in this system can be considered as an added value. The introduced scheme applies solar energy to supply thermal energy to a Brayton cycle. Two bottoming Rankine cycles are employed to empower a PEM electrolyzer using the residual heat from the gas turbine. The system is modelled using the Engineering Equations Solver for a comprehensive thermo-economic analysis. The exergy destruction analysis proved a significant loss of exergy by the solar field, illustrating the necessity to address this in future research. Afterwards, six design variables were selected and then optimized for the proposed system using the NSGA-II. Based on the TOPSIS approach, exergy efficiency, and capital cost rate, the objective functions were 22.2% and 272.6 $/h, respectively. Finally, a case study was performed to investigate the impact of solar irradiation and ambient temperature on system outputs. © 2021 The Author(s)
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Evidence shows that coronavirus disease 2019（COVID-19） can impact multiple bodily systems，with the cardiovascular system being commonly affected. In order to guide healthcare providers in diagnosing and managing cardiovascular issues related to COVID-19，the consensus group recommends：（1）Routine cardiac troponin testing is necessary for patients who are hospitalized or exhibit symptoms related to heart conditions after COVID-19 infection to evaluate potential myocardial injury and help detect any cardiac complications. Patients with myocardial injury not related to heart issues tend to have a poorer outcome. （2）Relatively few cases of acute myocarditis linked to COVID-19 have been reported，and individuals suspected of having myocarditis should be evaluated and managed based on risk stratification. （３）COVID-19 infection should be considered a risk factor for increasing the incidence of cardiovascular disease. All individuals who have been infected should adhere to a healthy lifestyle more strictly and implement appropriate primary or secondary preventive measures for cardiovascular disease.（4）For individuals who experience the persistence or emergence of new symptoms 3 months after the initial COVID-19 infection and have been experiencing these symptoms for at least 2 months，with no clear diagnosis of a cardiovascular disease through standard diagnostic tests，it is advisable to consider the possibility of "post COVID-19 condition". Rehabilitation should be given top priority for these patients. © 2023 Chinese General Practice. All rights reserved.
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During June to July, 2020, persistent heavy precipitation in the Yangtze River Basin (YRB) is resulting in extensive flooding, with over 158 fatalities and tremendous economic losses. This year's disastrous flooding extreme is exceptionally different from those of other years. It contains over 1000-year return period events (for 30-day cumulative precipitation) as observed in Anhui, Guizhou and Sichuan Provinces. The mean precipitation is 308 mm in July 2020, being 54 mm higher than that of July 1998, when serious floods affected the entire Basin causing tremendous socio-economic consequences. Compared with 1998, the short-term (e.g., 1 day) precipitation in YRB did not show significant increases, while the long-term (e.g., 30 days) cumulative precipitation increases significantly. The highest observed 30-day cumulative precipitation is 1221 mm (in Anhui Province) in 2020, while the highest one in 1998 was 1028 mm (in Jiangxi Province). We thus find that this persistent heavy precipitation is the main cause of flooding in 2020. At the same time, TGR may mitigate up 43% of upstream flood, although the main contributors to this year's YRB flood are in the middle and lower reaches. Affected by COVID-19, the number of people at risk in the threatened area are increased, and their capacities to mitigate the dual impacts of COVID-19 pandemic and flooding are hindered since (a) the flooding-caused mitigations may limit people's ability to prevent from virus spreading, and (b) the pandemic is retaining a large amount of migrant workers being within YRB and subject to flooding impacts. Overall, our main discovery is that, although the short-term precipitation in YRB did not increase significantly in 2020, the cumulative one increased significantly in 2020!. © 2022 ISEIS All rights reserved.
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Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease (2023 Report) (GOLD 2023) maintains the basic framework of GOLD 2022, but with major revisions in the definition, assessment, initial therapy and follow-up management of chronic obstructive lung disease (COPD) as follow: (1) Chapter 1: The definition and overview section was rewritten to propose a new definition of COPD, incorporating new background information, therapeutic strategies and classifications for COPD, with the addition of content on chronic bronchitis;(2) Chapter 2: Content on screening and case-finding of COPD has been included, the ABCD assessment tool has been revised to the ABE assessment tool (no further grouping of high-risk population of acute exacerbation of COPD based on symptom levels), information on imaging and computed tomography scans (CT) has been included in the diagnosis and assessment section;(3) Chapter 3: Recommendations for Streptococcus pneumoniae vaccination have been updated, information on therapeutic interventions to reduce COPD mortality has been included, issues related to inhalation delivery have been updated, content on inhaled medications adherence and remote rehabilitation has been included, information on interventional and surgical therapies of COPD has been expanded in the prevention and maintenance treatment section;(4) Chapter 4: Information on the selection of inhalation devices has been included, information on initial drug therapy and follow-up drug therapy has been updated in the management of stable COPD section;(5) Chapter 5: A new definition of and set of acute exacerbation of COPD assessment parameters have been proposed, information on differential diagnoses of acute exacerbation of COPD has been expanded in the acute exacerbation of COPD section management;(6) Chapter 6 and 7: Updating content on COPD and complications (Chapter 6), COPD (Chapter 7) and COVID-19 based on the latest evidence. The above updates will be an important guide to the clinical management of COPD. © 2023 Chinese General Practice. All rights reserved.
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Clinical importance: Novel coronavirus disease is spread worldwide with considerable morbidity and mortality and presents an enormous burden on worldwide public health. Due to the non-stationarity and complicated nature of novel coronavirus waves, it is challenging to model such a phenomenon. Few mathematical models can be used because novel coronavirus data are generally not normally distributed. This paper describes a novel bio-system reliability approach, particularly suitable for multi-regional environmental and health systems, observed over a sufficient period of time, resulting in a reliable long-term forecast of novel coronavirus infection rate. Traditional statistical methods dealing with temporal observations of multi-regional processes do not have the advantage of dealing efficiently with extensive regional dimensionality and cross-correlation between infection rate and mortality. Objective: To determine extreme novel coronavirus death rate probability at any time in any region of interest. Traditional statistical methods dealing with temporal observations of multi-regional processes do not have the advantage of dealing efficiently with extensive regional dimensionality and cross-correlation between different regional observations. Design: Apply modern novel statistical methods directly to raw clinical data. Setting: Multicenter, population-based, medical survey data based bio statistical approach. Main outcome and measure: Due to the non-stationarity and complicated nature of novel coronavirus, it is challenging to model such a phenomenon. Few mathematical models can be used because novel coronavirus data are generally not normally distributed. This paper describes a novel bio-system reliability approach, particularly suitable for multi-country environmental and health systems, observed over a sufficient period of time, resulting in a reliable long-term forecast of extreme novel coronavirus death rate probability. Conclusions and relevance: The suggested methodology can be used in various public health applications, based on their clinical survey data. © 2023, Indian National Science Academy.
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The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a tremendous burden on public health and world economies. An efficient host immune response to acute SARS-CoV-2 infection requires rapid and early activation of the innate immune system. Natural killer (NK) cells represent a critical component of the innate immunity. Here, the appearance of CD56-CD16+ NK cells and unconventional CD56dim CD16neg NK cells during the course of SARS-CoV-2 infection, and the phenotype and effector functions of NK cells during SARS-CoV-2 infection were summarized. The involvement of the dysregulated NK cells in the immunopathogenesis of the coronavirus disease 2019 (COVID-19) and clinical trials of adoptive NK cell-based therapies against COVID-19 were also discussed. © Wolters Kluwer Health, Inc. All rights reserved.
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How infectious diseases shape individual minds and behaviors has been of interest to researchers. We conducted four studies to examine whether the threat perception of the COVID-19 pandemic was positively related to pro-environmentalism. Study 1 (N = 1,508) showed that individuals' threat perception of the pandemic was correlated with their pro-environmental behaviors. Study 2 (N = 241) clarified the causality by manipulating threat perception and found that individuals with high (vs. low) threat perception reported higher pro-environmental willingness. Study 3 (N = 406) revealed that awe for nature mediated this relationship. Study 4 (N = 405) replicated Study 3 more than two years after the outbreak and demonstrated the findings were robust regardless of decreases in infection fear. These findings suggest that the COVID-19 pandemic provides individuals with an opportunity to reconsider the way they treat nature. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
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The outbreak of COVID-19 provides a rare opportunity for the implementation of the carbon tax. To determine which stage is the most appropriate for introducing the policy, a simulation model based on China's panel data is established to analyze the impact of the carbon tax on government revenue and residents' income from five scenarios. A new GM-SD modeling method is proposed to ensure the accuracy of the model. The results show that the impact of the carbon tax on the government and the public is significantly different at different stages, and even the implementation of the carbon tax in the early stage of COVID-19 will reduce the government's tax revenue. The score analysis of government tax revenue, residents' surplus disposable income, residents' emotional value, and government administrative power finds that the middle period of COVID-19 is the best time to implement the policy. In addition, a more detailed analysis of five aspects, including total population, energy consumption, and national income, shows that the best time to implement the carbon tax policy is when the damage degree of COVID-19 is moderate. The analysis results can provide a reference and basis for China to introduce the carbon tax in the event of similar events as COVID-19, and have reference significance for other countries that have not implemented a carbon tax. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
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By April 28, 2020, the global pandemic of COVID-19 has resulted in over 3 million infections and more than 200, 000 deaths. As the epidemic of COVID-19 has been basically controlled in China, the asymptomatic infection becomes one of most serious challenges for "External defense input, internal defense rebound" currently. Studies have shown that patients with asymptomatic infections are highly contagious in the early stage, most of whom are in the pre-symptomatic stage. Children and pregnant women have a higher incidence of asymptomatic infections, but the impacts are not yet clear. This article reviews the definition, epidemiological characteristics, contagiousness, viral shedding and cause of persistent positive nucleic acid in asymptomatic patients. Active detection of nucleic acids and antibodies and timely diagnosis and treatment of asymptomatic cases are the critical issues for the prevention and control of COVID-19.Copyright © 2020 by the Chinese Medical Association.
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By April 28, 2020, the global pandemic of COVID-19 has resulted in over 3 million infections and more than 200, 000 deaths. As the epidemic of COVID-19 has been basically controlled in China, the asymptomatic infection becomes one of most serious challenges for "External defense input, internal defense rebound" currently. Studies have shown that patients with asymptomatic infections are highly contagious in the early stage, most of whom are in the pre-symptomatic stage. Children and pregnant women have a higher incidence of asymptomatic infections, but the impacts are not yet clear. This article reviews the definition, epidemiological characteristics, contagiousness, viral shedding and cause of persistent positive nucleic acid in asymptomatic patients. Active detection of nucleic acids and antibodies and timely diagnosis and treatment of asymptomatic cases are the critical issues for the prevention and control of COVID-19.Copyright © 2020 by the Chinese Medical Association.